Hundreds of thousands of bitcoins are missing

On Friday, Japan-based Mt. Gox filed for bankruptcy protection. Appearing before Japanese media in Tokyo, Mt. Gox CEO Mark Karpeles apologized for “the troubles” he had caused Mt. Gox customers. Karpeles said that a vulnerability in the bitcoin exchange’s systems had led to the disappearance of 850,000 bitcoins, the Associated Press notes.

At current a current trading price of about $500 per bitcoin, that would put Mt. Gox’s bitcoin losses at north of $400 million. No one yet knows if the bitcoins were stolen from Mt. Gox, or somehow lost due to technical problems.

Japanese financial authorities say that they have no regulatory authority over bitcoin exchanges.

Trouble at Mt. Gox surfaced earlier this month when the exchange halted bitcoin withdrawals from customer accounts. At the time, the bitcoin exchange attributed the move to a technical glitch in its software, insisting that it was only a temporary measure.